The big three#

Which cloud service provider offers the best managed FaaS solution? Is it Azure, AWS, or Google Cloud?

Note: We’ll exclude on-prem solutions. Similarly, we don’t cover all compute providers, but only the “big three.”

There are quite a few criteria we could use to compare FaaS services. Many will depend on the use cases, experience, needs, and so on and so forth.

Let’s start with the supported languages.

Note: The number of supported languages may have increased since this course was written (July 2020).

Google Cloud Functions, Azure Functions, and AWS Lamda services support the languages that follow.

According to those lists, Google Cloud Functions is the apparent loser, and both Azure and AWS share the trophy. Nevertheless, that often does not matter. The question is not which service supports more languages, but whether our preferred language is available. Also, it’s not only about our preferred language. Some languages are better suited to functions than others.

We should think twice before using a language that needs significant time to initialize processes. In a “normal” situation, waiting for a second for a Java or C# process to start might be okay. After all, one second is almost nothing considering that a process might run for hours, days, or even months. But, in a situation where each request initializes a new instance of the application (function), the initialization time is essential. Even though FaaS providers have managed to overcome some of the hurdles around that issue by keeping functions “warm” for a while, those are still improvements and not real solutions.

JavaScript, Python, and Go are all well suited for functions. They start quickly and work well on a small codebase. Still, the supported languages might influence the decision of where to run functions.

Deployment time#

We can also compare managed FaaS solutions by the amount of time it takes to deploy a function.

Taking all this into account, we can say that AWS is the clear winner. Nevertheless, the extra minute to install or update a function may still not matter much.

While we are on the subject of installations and updates, we might comment on the complexity of performing those operations. But that’s also irrelevant since we didn’t use a provider-native way to create and deploy functions. Instead, we used the Serverless Framework, which works more or less the same way everywhere. To be more precise, with the Serverless Framework, deploying a function is as easy as it can get wherever we run them. So, we can’t use the complexity of deployment operations as an argument that the FaaS of one provider is better than the other.

Note: Since we’re talking about the cost, we should stress that FaaS tends to be very expensive when running at scale. Our previous statements are aimed at comments about the differences in pricing between the major providers, and not about the cost-effectiveness of using managed FaaS in general.